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major reference

The
Theaetetus considers the question “What is knowledge?” Is it perception, true belief, or true belief with an “account”? The dialogue contains a famous “digression” on the difference between the philosophical and worldly mentalities. The work ends inconclusively and may indeed be intended to show the limits of the methods of the...

criticism of sensualist theory of knowledge

In his later dialogues, especially the
Theaetetus, Plato criticized an empiricist theory of knowledge, anticipating the views of 17th-century English philosophers such as Thomas Hobbes (1588–1679). In the
Timaeus, Plato tried to construct a complete system of physics, partly employing Pythagorean ideas.

discussed in biography of Theaetetus

...with Theodorus of Cyrene. He taught at some time in Heraclea (located in present-day southern Italy). Plato made
Theaetetus the chief subject of two dialogues—
Theaetetōs (
Theaetetus) and
Sophistēs (
Sophist)—the former being the major source of information about
Theaetetus’s life, including his death in a battle between Athens and Corinth...

epistemology

Plato’s search for definitions and, thereby, forms is a search for knowledge. But how should knowledge in general be defined? In the
Theaetetus Plato argues that, at a minimum, knowledge involves true belief. No one can know what is false. A person may believe that he knows something, which is in fact false, but in that case he does not really know, he only thinks he knows. But...

presentation of Heracleitus’ doctrine of flux

...predecessor Heracleitus, who flourished at about the beginning of the 5th century
bc, the doctrine that the world of sensible things is a world of things in constant flux; as he put it in the
Theaetetus, nothing
is in this world because everything is in a state of becoming something else. Forms were needed to provide stable objects for knowledge as well as to answer the...